The widespread adoption of cellular technologies in recent years has created a corresponding burden on existing cellular networks. As a result, alternative approaches to routing communication sessions are being considered to reduce network congestion. Such approaches include device-to-device (D2D) sessions, where the session traffic is not routed through the network, but instead, directly between the devices themselves. Known approaches to D2D sessions include the implementation of a session-set-up filter (SSUF) as a cellular network entity to assist in the initiation of D2D sessions.
In one approach, the SSUF not only directly assigns and supervises the use of inter-device communication channels among devices, but also identifies which devices are located within inter-device channel communication range of each other. In this approach, the SSUF typically administers the inter-device communication channels to manage interference, device location information, and handover requests between D2D and conventional wireless communication technologies. In another approach, the SSUF enables the broadcast of inter-device communication channel availability information within a cell to D2D-enabled devices, which then use the broadcast information to initiate a D2D session on their own. In this approach, the SSUF assists neighboring devices in locating other devices that are within inter-device channel range. For example, a device wishing to use inter-device channels for communication would send its identification and the identification of any desired devices to the SSUF. In response, the SSUF would then broadcast a page message to request the desired devices to listen to the inter-device channel for communications from its neighbor.
However, one obstacle to the realizing the benefits of D2D sessions is the fact that a device is typically not aware of the location of other devices that are capable of using an inter-device channel for communication. Furthermore, D2D session set-ups performed by a network entity (e.g. SSUF) may result in delays that are noticeable to the user of the devices. Moreover, some D2D sessions may not be successful due to signal interference or shadowing of the radio signals, despite the fact that appear to be possible due to device proximity.